Not quite a bumper sticker, but in the same vein...
An Australian lady climbed over the fence around Binky the Polar Bear's pen. Obviously the bear figured this was a free meal, and mauled her, but fortunately the silly woman managed to get away. When the commotion was over, a photographer shot a picture of her tennis shoe hanging from the bear's mouth.
That photo graced a lot of T-shirt's that read:
<b>Send more tourists - this one got away</b>
True story, I'm not making this up.
http://gdl.msu.edu/%7Evanhoose/humor/0155.html
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